some historians to suggest that before the Mongol invasion of Rus' the level of literacy in the country might have been considerably higher than in contemporary Western Europe. Koch / Icebreaker The koch was an ancient form of icebreaker, being a special type of one or two small wooden sailing ships with a mast, used for voyages in the icy conditions of the Arctic seas and Siberian rivers. The koch was developed by the Russian Pomors in the 11th century, when they started settling on the White Sea shores. The koch's hull was protected by a belt of ice-floe resistant flush skin-planking (made of oak or larch) along the variable water-line, and had a false keel for on-ice portage. If a koch was in danger of being trapped in the ice-fields, its rounded bodylines below the surface would allow for the ship to be pushed up out of the water and onto the ice with no damage. In the 19th century similar protective features were adopted to modern icebreakers. Gudok The gudok is an ancient East Slavic string musical instrument, played with a bow. It usually had three strings, two of them tuned in unison and played as a drone, the third tuned a fifth higher. All three strings were in the same plane at the bridge, so that a bow could make them all sound at the same time. Sometimes the gudok also had several sympathetic strings (up to eight) under the sounding board. These made the gudok's sound warm and rich. It was also possible to play while standing or dancing, which made it popular among skomorokhs. The name gudok comes from the 17th century, however the same type of instrument existed from 11th to 16th century, but was called smyk. Medovukha Medovukha is an old Slavic honey-based alcoholic beverage very similar to mead, but much cheaper and faster to make. Since the old times the Slavs exported the fermented mead as a luxury product to Europe in huge quantities. Fermentation occurs naturally over 15 to 50 years, originally rendering the product very expensive and only accessible to the nobility. However, in the 11th century East Slavs found that fermentation occurred much faster when the honey mixture was heated, enabling medovukha to become a commonly available drink in the territory of Rus'. In the 14th century, the invention of distillation made it possible to create a prototype of